Multi-stage lint cleaner



March 4, 1958 H. G. Moss MULTI-STAGE LINT CLEANER Filed Oct. 15, 1956 INVENTOR bray/e d fl/ass V v ATTORNEYS Unitd States Pa re {Thi inv ntion i relates to lint cotton cleaners of the t'y p etin which, the cottonin theform ofathm batt ,progressivelyfed endyvise into the I peripheral path of a vtrapidly revl'llvingtoothed cylinder whichpulls the fiber -from'the endt o'f thebat and present circumferentially to cleaninginstrurnentalities, the cotton being; removed from the toothed cylinder b'y, sui tz 1b le doflin g means.

,One,of .the.objects. of tt heinvention 'isthe provision of a l int cotton cleaner of the type described, in which a thin bat from a bat I forming condenser-passes .between a set of drawing rolls onits;way to the toothed. cylinder, by which rollsr-it is drawn still thinner sothat the edge of theybattpresented to the cylinder is a: thin fringe, resulting in each tooth-softhe cylinder. catching onlya few of the cotton fibers so thatfarverythorough cleaning of the .lint isi-accompl ished. I

- Another object of theinvention i the provision of a ,double cleanervof the type describedgin which the cotton is -successively,c leaned -;upon two toothed cylinders, the 1 transfer from oneitov the other being efiected by anjintermediatetransfer drum, the-relative peripheral speeds :of the cylinders :beingtsuch' that "the cottonisucombed adjacentthe -points- -of tangency of the cylinders with, the transfer drum, Whereby thetfibersare brought into a relative position of parallelism. I

:;Stillanotherobj'ect :Ofthe invention is the'use of air in;=precisely directed jets, :for assisting in the transfer of the cottonvf-rom the first-toothed cylinderto thettransf er wldrum and from the transfer "drum to thesecond toothed cylinder, the EfibEI'S bcing scoured -by frictional contact -vwith=thejetsas well asbeing arranged parallel. v

r A still further objectqof the invention is the control :.and inhibition of spurious and conflicting air currents generated by the rotation of the toothed cylinders and wtransferdrum, so as to prevent the fibers from being ,.subjected.to turbulence, which is a primary cause of .nepping.

Lubbock, Tex assignor of one-fourth Y 7 and a partiuonlt-whwh divides the lower part'of -the Otheriobjects of the invention will appear as the fol- -lowingdescription,of a practical embodiment thereof I proceeds. r

-In vthe drawing which accompanies and forms a part 7 O'fqthfi following specification:

The sole figure is a side sectional view of a lint cotton cleaner embodying the principles of the invention, the

section being taken in a vertical plane.

Since inthe illustrative example the toothed cylinders 'are shown as saw cylinders, they will hereinafter in the specification be referred to as saw cylinders, 'but this does not. rule out the eligibility of other types of toothed cylinders as equivalents in carrying out the purposes" of the invention.

Referring'nowoin detail ,to the drawing, the general adapted to vregister with the discharge opening of ia super-posed. bat. forming condenser such .:'as. the convenr'i atented Mar. 4, 1958 tional typej in which the c0tton"'c'o-llects-' on the exterior of a perforated cylinder evacuated on the inside, from Which 'it' is continuously scraped inrtheform of a thin coherent bat. The bat enters through the opening2 into the cleaner, I pas'singfthrough successivepairs of"drawirrg 1 rolls :4 and 5 thelower pair rotating at j a faster speed thus reducingthe thicknessof the i'th'at the rolls of the 'lower pair jtemete closely ;spa djthan those "of'the ,up'per; pair' to njaintain'ffjr ictional ,Jgri join the bat, Beneath the lower pair of"dra'wing rolls isthefeedrollh, which in cooperation withthefeed bar/Z, presents the ,end of -,the, biat to the saw c linders, ,Iheithinnthgrof the batputslittin 'betterconditiontofdelivefijit. to ,thesjaw ar'Idf-atthe same time has teiiden cyto decrease themattiness.orfluxnpine'ss of the sample. by "stretching out the thin, spots, jgivinga "more unifornidensityt in "the bat thickness.

jacent ,arc' the reea reu, and narrowly ,spaced there- 7. from thr'ongh which space ;th e ,-t. in. bat is conducted by t e feed roll. he endtof thebat WhlChglS reduced to a mere l frinjg is .continuously c ombed offtby the teethlof thcrsaw hnderfi, the bat being subject to an abrupt directionphangeabout the ,nose; 10 ofthe feed bar Which prevents the sakwteeth from tearing oii lumps of cotton extending-up into, the ,space bet-weenthe feed bar and feed rpll provided that the batds held between-vsaid bar and roll withgunifprrn :frictiona1 .-pressur,e ,across -iits entire Width,WiI iQh WDu1dbe thernorm'al condition-'except where the b at might-The affected by thin-places,

where {the ,frictional pressure woulidebe IGlQtiVQlYillgilt. The saw cylinder {5 s; preferably rotated atz'such's-speed Which lie's close-to gt'hegperipheryz'ofithe'tsaw "cylinderyits functiontbeing to-oseat the cottonipo's'itively intoithe saw Y teeth. Beyond the fiat face-'11 the 'feedl b'ar ha s a faoe 12 divergent in ;a idirection tawayfrom the saw, providing a space into which the fibers which a're u'nder restrained centrifugal force beneath the face 11 Tsnapout as they pass the shoulder 1 2 at the'end of the tace l'l'. Aconsiderable portion ofthe motes and" trash-"are thrown 6ft.

'from the lint in this snapping movement,-'and"the "fibers 'stand out centrifug'al ly in position to "be impactively contacted by the grid b'ars13.

'aid grid'bars form'a series that encompa's'se's thes-aw cylinder through anf'arc extending between the feledbar casing 1, forming a trash chamber '15 to the left or said partition underlyingthe grid 'bars, which chamber converges downwardly tofa niote and'trash ate-15', which is maintained under suction. The cotton tifbersstand out under centrifugal urge in the spaces between the grid bars and are kno'cke'ddlat uponcontacting thejgrid bars, giving upmorevof their trash through theinertia of. the trash. 7 The grid bars are's paced suflieiently closet'o'keep the cotton traversing'the spaces firotnn isihg to the ileht that some of t 'ht'fly art and be lo'stwllh the t st.

in the statement of objects of the invehtion th mentalgeffect' was referred "to, of spurious airfc'u'r-rcnts creatingfturbulencewithin the cleaner. Such air irrents 'are for the n'iost part generated by the re 7 the saw. cylinders and tr afnsferldrjuni, Whichare tively large d ameter..and..driven at high speed. IByway of illustration, be said -that .the a t find V i be twenty inches in diametereand the transfer'id rn sit;- ninc s, t ese di nsions f c urse methaner a to the invention. I I

There is a narrowgperipheralspace between the S111! face of the saw cylinder above which the teeth rise, and the outer boundary of the coating of cotton on the teeth from which the air is somewhat evacuated through.

from this peripheral space, such spurious currents are suppressed and turbulence within the chamber reduced to a minimum. The effect of turbulence is to impart uncoordinate or desultory movements to adjacent fibers, so that they tangle or knot or twist, becoming thereafter inseparable by any known means, and forming thick points or neps in the yarn and in the fabric woven therefrom.

Referring to the drawing, it will be noted that the part of the casing 1 which contains the drawing rolls and feed roll is substantially isolated by a back plate 16, forming part of the casing to the right of the drawing rolls, and that the lower end of said back plate is con tinuouswith a curved shield 17 substantially concentric with the saw cylinder 8 through an extensive are above and doffing station 18 and closely spaced with respect to the periphery of the saw cylinder. The lower end 19 of the shield 17 is deflected inwardly toward the saw cylinder so that it clears the teeth by a very small amount, for example, from one-sixteenth to one-eighth of an inch, whereby entry of air at the lower end of the shield is to a great extent prevented. However, as there is no cotton on the teeth in this section of the saw cylinder to act as a packing against the shield, some air will enter and discharge from the upper end of the shield. The part of the bat exposed between the pairs of drawing rolls is particularly vulnerable to eddy currents, so a flashing has been provided, consisting of a flexible plate 20 of rubber, for example, fixed to the back plate 16, and having its free end wiping against the feed roll 6. This flashing elfectually prevents air currents which issue from the upper end of the shield 17 from reaching the region within the casing above said flashing and playing upon the exposed portion of the bat. The peripheral surface of the feed roll 6 is preferably spaced within one-sixteenth to one-eighth inch of the surface of the saw cylinder, so that any air current from the saw cylinder reaching the fringe of the bat is minimized.

At the dofling station .18, the saw cylinder 8 is tangent to a transfer drum 21,which in the illustrative example is also a saw cylinder with the teeth pointing in the same direction as those of the saw cylinder 8, the peripheries of the two cylinders traveling in the same direction in the region of tangency and the transfer drum rotating at the greater peripheral speed. Below the point of tangency, the saw cylinder 8 is provided with a pan or shield 22, which extends from a point adjacent the dofiing stationto a point adjacent the series of grid bars, and being designated from its proximity to the grid bars, as the grid pan. As shown, it is connected to the partition 14, but this is not vital. It lies close to the periphery of the saw cylinder 8 and is farther away at the partition end 23 than at the end adjacent the point of tangency of the saw cylinder and transfer drum.

Since the saw cylinder 8 is loaded with cotton throughout the are covered by. the grid pan, the cotton effectively packs the end 23 against entrance of air, while the movement of the cotton through the gradually increasing space creates a substantial vacuum within the grid pan. Said grid pan is provided with a flat face 25, extending downwardly from its end 24, which in conjunction with theadjacent side of the transfer drum 21 and also with the face 26 of a pan 27 that underlies the transfer drum, definesa nozzle capable of delivering a precisely directed jet of air to the cotton at the point of transfer. The rapid movement of the saw cylinder 8 extends the vacuous condition which permeates the cotton which coats the saw, upwardly beyond the end 24 so that the inducted air jet does not turn about the end 24 and go down between the grid pan and saw cylinder, but advances straight forward, expanding into the space 33 between the saw cylinder and transfer drum, and assists in transferring the cotton from the teeth of the saw cylinder to the transfer drum by diminishing the pressure of the teeth against the cotton which they carry. Since the peripheral speeds of the saw cylinder and transfer drum are greater than the velocity of the air jet generated through their rotation, the effective movement of the air is downward frictionally against the lint, and tends to comb the fibers into parallelism. It will be readily understood that there would be an upward air flow in the space 33 and past the teeth of both saw cylinder and transfer drum at the point of tangency in the absence of the grid pan 22 and the nozzle defining faces 25 and 26, but the flow would be derived from the peripheral currents induced by the saw cylinder and transfer drum, which would come together at a conflicting angle, causing eddy currents and turbulence in the space 33, which it is the object of the present invention to suppress.

The purpose in having the shield 22 closer adjacent the partition 14 than adjacent the doffing point is that it has been found that the entering side of the shield should be spaced farther from the saw than the leaving side, in order for the air generated by the saw cylinder to be gradually suppressed and the cotton somewhat expanded so that it can be more or less opened by the impinging air jet from the nozzle at 25.

The transfer drum 21, in the form shown, is a saw cylinder rotating in a direction opposite to that of the saw cylinder 8, with the abrupt faces of the teeth leading, so as to strip the cotton from the saw cylinder 8. The transfer drum is the means for conveying the cotton from the saw cylinder 8, which with its associated cleaning instrumentalities, represents the first cleaning stage, to the saw cylinder 28 which with its correlated cleaning means, represents the second cleaning stage, the last mentioned saw cylinder having its teeth travelling in the same direction at the point of tangency as the teeth on the transfer drum, the latter teeth having their abrupt faces leading so as to strip the lint from the transfer drum. The saw cylinder 28 has a greater peripheral speed than the transfer drum.

A driven roll 29, which is preferably but not necessarily toothed, is mounted above the transfer drum 21 tangent thereto at the peak of the upper arc of its path of rotation, the purpose of which roll is to seat the cotton firmly in the teeth of the transfer drum. Between the roll 29 and the points of tangency of the transfer drum with both saw cylinders, are the arcuate shield plates 30 and 31. These are concentric with the transfer drum and lie close to the periphery thereof, and as the transferdrum is loaded with cotton in the arcs covered by these shields, there is a substantial exclusion of air currents travelling beneath them in a circumferential direction, and a vacuous atmosphere permeates the cotton coating, inducing a precisely directed air jet through the nozzle defined between the fiat end flange 32 of the shield plate 30, and the roll 29. This air jet blows into the space 34, but since the transfer drum is necessarily travelling faster than any air movement that it can create, it follows that the lint cotton passes through the jet and in the direction thereof at the point of transfer, the 'fibers becoming arranged parallel in the same manner as has already been described with respect to the induced air jet at the space 33.

Such of the air that gets by the roll 29 at its point of tangency escapes through the space 35 between the roll 29 and the adjacent end of the shield plate 31. The projection 19 which has hereinbefore been referred to as restricting the entrance of air between the saw cylinder 8 and the shield 17,has another function, as a diverter to direct cotton which may not be firmly attached to the transfer drum, into the passage between the shield plate 35 and the dofling drum, where it will eventually become as the air inlet 51 becomes choked, the action of the doffer is to take in more air at the nozzle formed at 62, to satisfy the actual need of the dolfing operation. Consequently, as this air has no place to go except to the inlet opening 54, it chooses this path and carries the cotton outside of the machine to a suitable bin, not shown, provided to receive it. The above refers, of course, to an emergency functioning of the apparatus.

While I have in the above description disclosed a practical embodiment of the invention, it will be understood by those skilled in the art that the specific details of construction and arrangement of parts are by way of example and not to be construed as limiting the scope of the invention.

What I claim is:

1. Apparatus for cleaning lint cotton in successive stages comprising, a first stage saw cylinder, means for progressively presenting cotton in bat form, endwise to said first stage saw cylinder, a second stage saw cylinder, means for dotting the cleaned lint from said second stage saw cylinder, a transfer cylinder between said saw cylinders tangent to both, receiving cotton from said first stage saw cylinder and transferring it to said second stage saw cylinder, at the respective points of tangency, means operatively related to adjacent cylinders at each point of tangency, at the sides of said respective points of tangency approached by the cotton laden portions of said first stage saw cylinder and said transfer cylinder for inhibiting convergent air currents travelling circumferentiallyof said adjacent cylinders, and forming nozzle passages for directing air jets toward said respective points of tangency, a roll tangent to said transfer cylinder at an intermediate point in the cotton laden arc of its path of rotation for setting the cotton on said transfer cylinder, and a'shield closely embracing said transfer cylinder through an are extending from a point adjacent the retreat side of the point of tangency between said first stage saw cylinder and said transfer cylinder, to a point adjacent said roll, said shield being spaced from said roll to permit entrance of air to the point of tangency of said roll with said transfer cylinder, induced by rotation of said roll, for paralling the fibers outstanding from said transfer cylinder.

2. Apparatus for cleaning lint cotton in successive stages, as claimed in claim 1, the transfer cylinder being toothed.

3. Apparatus for cleaning lint cotton in successive stages comprising, a first stage saw cylinder and means for feeding cotton thereto, a second stage saw cylinder, a doifer for removing the lint from the second stage saw cylinder, and a transfer cylinder between said first and second stage saw cylinders tangent to both, receiving cotton from the first stage saw cylinder and transferring it to said second stage saw cylinder, a series of spaced grid bars in operative proximity to said first stage saw cylinder, beyond said feeding means and a similar series of spaced grid bars operatively related to the second stage saw cylinder beyond the transfer point of cotton to said second stage saw cylinder, a shield pan underlying said transfer cylinder having its edges in close relation to the periphery of said transfer cylinder for suppressing air flow circumferentially of said transfer cylinder and maintaining a vacuous atmosphere between said shield pan and the part of the transfer cylinder carried thereby, said shield pan being a collector for loose trash dropped from the cotton onto the surface of said transfer cylinder, said shield pan having a trash discharge opening, a vacuum retaining gate valve controlling said opening for discharging the trash into trash disposal means, a grid shield closely embracing a cotton laden portion of said first stage saw cylinder between the associated series of grid bars and the point of tangency between said first stage saw cylinder and said transfer cylinder, said grid shield cooperating with the adjacent end of said shield pan to form a nozzle passage to direct an air jet to said point of tangency, said grid shield being instrumental in creating a vacuum in the cotton passing said shield which draws an air jet through said nozzle passage.

4. In a cleaner for Zint cotton, a casing housing the elements hereinafter defined, a toothed cylinder to which cotton is fed and a dofier cylinder with spaced rows of brushes tangent to said toothed cylinder, a series of spaced grid bars in operative proximity to said toothed cylinder beyond the feeding point, a grid shield closely embracing a cotton laden portion of said toothed cylinder beyond said series of grid bars, a dotfer shield underlying said doffer cylinder having its end which is, adjacent said grid shield substantially contiguous to the path of travel of the ends of said brushes, for suppressing circumferential air flow through the space underlain by said doffer shield, the latter cooperating with said grid shield to form a nozzle passage for directing an air jet toward the point of transfer betwen said toothed cylinder, and said doffer cylinder, said grid shield being instrumental in creating a vacuum in the cotton passing said shield, which vacuum draws an air jet through said nozzle passage, a lint flue opening into said casing adjacent the end of said doifer shield remote from said nozzle passage and below said dotfer, an air inlet opening into said casing over said lint fiue for directing an entering air fiow toward said lint flue, and an adjustable plate at the said remote end of said doffer shield settable to substantially inhibit the entrance of air into the space covered by said doffer shield and to prevent the vacuum maintained in said space from diverting lint from said lint flue.

5. Apparatus for cleaning lint cotton in successive stages comprising, a first stage saw cylinder, means for progressively presenting cotton in bat form endwise to said first stage saw cylinder, at second stage saw cylinder, means for doffing the cleaned lint from said second stage saw cylinder, a transfer cylinder between said saw cylinders tangent to both, receiving cotton from the first stage saw cylinder and transferring it to the second stage saw cylinder, at the respective points of tangency, pairs of adjacent arcuate shields closely embracing the arcs of adjacent cylinders at each point of tangency, at the sides of said respective points of tangency approached by the cotton laden arcuate portions of said first stage saw cylinder and said transfer cylinder, for inhibiting convergent air currents travelling circumferentially of said cylinders, the shields of each pair being separated at their adjacent ends, forming nozzle passages for directing air jets to the corresponding points of tangency, the respective shield of each pair which embraces the cotton laden portion of the corresponding first stage and transfer cylinders, producing a vacuum in the confined cotton effective beyond the ends of said shields proximate the corresponding points of tangency, to induce an air jet through the corresponding nozzle passages to comb the cotton and assist in itstransfer, a roll tangent to said transfer cylinder at an intermediate point in the cotton laden arc of its path of rotation for setting the cotton on said transfer cylinder, and a shield closely embracing said transfer cylinder through an are extending from a point adjacent the retreat side of the point of tangency between the first stage saw cylinder and transfer cylinder to a point adjacent said roll, said' shield being spaced from said roll to permit the entrance of air to the point of tangency of said roll with the transfer cylinder, induced by rotation of said roll, for paralleling the fibers outstanding from said transfer cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 394,640 Brott Dec. 18, 1888 1,426,437 Woolridge Aug. 22, 1922 2,064,602 Harris Dec. 15, 1936 2,704,862 Moss Mar. 29, 1955 2,747,235- Wallace May 29, 1956 

